1. Technical Field
The subject matter described here generally relates to wind turbine tower structures and methods of forming composite wind turbine tower structures.
2. Related Art
A wind turbine is a machine for converting the kinetic energy in wind into mechanical energy. If the mechanical energy is used directly by the machinery, such as to pump water or to grind wheat, then the wind turbine may be referred to as a windmill. Similarly, if the mechanical energy is converted to electricity, then the machine may also be referred to as a wind generator or wind power plant.
Wind turbines are typically categorized according to the vertical or horizontal axis about which the blades rotate. One so-called horizontal-axis wind generator is schematically illustrated in FIG. 1 and available from General Electric Company. This particular configuration for a wind turbine 2 includes a tower 4 supporting a nacelle 6 enclosing a drive train 8. The blades 10 are arranged on a hub 9 to form a “rotor” at one end of the drive train 8 outside of the nacelle 6. The rotating blades 10 drive a gearbox 12 connected to an electrical generator 14 at the other end of the drive train 8 arranged inside the nacelle 6 along with a control system 16 that receives input from an anemometer 18.
As the size of blades 10 has increased, so has size of the towers 4. Current wind turbine towers 4 are typically fabricated from steel sheets that are manufactured at a remote location and then assembled at the site of the turbine 2. However, these materials are often difficult and expensive to manufacture, transport, and assemble. While using composite material can reduce the weight and transportation costs for the components of the tower 4, conventional techniques often still require transportation of multiple pieces that must then be joined together at an outdoor construction site.